Power-transmitting means



W. BUHL.

POWER TRANSMITTING MEANS.

APPLlCATlON FILED NOV. 26. 1918.

1,347,076. Patented July 20, 1920.

2 SHEETSSHEET I.

N w INVENTOR.

ATTORNEY.

W. BUHL.

POWER TRANSMITTING MEANS.

APPLICATION FILED NOV- 2'6, I918.

llll,

2 SHEETSSHEET 2. 1 6.

Patented July 20, 1920.

INVENTOI? 22 Z1 23 75 W WM ATTORNEY.

UNITED STATES PATENT OFFICE.

WILLIAM BUHL, 0F FLUSHING, NEW YORK, ASSIGNOR TO BULKRUG MACHINECORPORATION, A CORPORATION OF NEW YORK.

POWER-TRANSMITTING 'MEAN'S.

Specificationof Letters Patent.

Patented July 20, 1920.

To all whom it may concern:

Be it kngwnlhatl, WILLIAM BUHL, a

citizen of the United States," and a resident of Flushing, in the countyof Queens and State of New York, have invented an Improvement inPower-Transmitting Means, of which the following is a specification.

My invention relates to means fo'rtransmitting power, and it has for itsobject generally to provide a simplified and improved construction ofsuch means whereby rotary motion may be converted into reciprocatorymotion and the power incident to such rotary motion appliedrectilinearly. The principle of my invention is also applicable to aconstruction in which rectilinear motion is converted into a rotarymotion and the power applied as a result of the latter movement insteadof directly from a rectilinearly moving part.

In the drawing I have illustrated and shall describe herein my inventionas employed in a riveting machine, but it will be understood that it maybe employed in machines of other kinds and for other purposes. a Myinvention is an improvement of the construction shown in United StatesPatent No. 878,152, issued February 14, 1908, and its object morespecifically stated is to provide a simplified construction of machineof the character illustrated in the said patent.

One of the objects of my invention is to provide a construction in whichthe hammer which operates upon the tool, whether it be a riveting tool,a rock drill or other tool, is integral. with the yoke,the tool,however, being a separate, non-integral part.

A further object is to provide a construction in which and whereby thestroke of the hammer may be varied within certain limits withoutinterfering with the operation of the device or machine and without in.any

way injuring the same; and also in which ,VlClBd with holes orunderstood and its preciated, reference should be had to theaccompanying drawing in which I have illustrated a constructionembodying one form of a convenient embodiment of my invention.

In the drawing Figure 1 is a View partly in front elevation and partlyin longitudinal section, the section being taken on the line 11 of Fig.3;

Fig. 2 is a view in front elevation of the machine shown in Figs. 1 and3;

Fig. 3 is a view in side elevation of the same;

Fig. 4 is a view in front elevation of the yoke member and the crank pinand crank disk shown in Fig. 1 and indicates by dotted lines thedifferent positions of the cam slot in the yoke member; and

Fig. 5 is an enlarged view in front elova tion of a portion of the yoke,showing more clearly a detail of the construction;

Fig. 6 is a horizontal, transverse, sectional View of the machine; and

Fig. 7 is a view taken on the line 7-7 of Fig. 6 and being partly invertical longitudinal section and partly in side elevation.

Referring to the drawing :1 designates the main or body portion of acasing in which is situated the yoke or cam member 2 and the crank disk3, the latter being mounted upon and being integral with the inner endof a shaft 4 supported in a bearing closing the opening 6 formed in thecasing 1. The crank disk may be otherwise than integrally connected withthe shaft 4. The casing 1 is provided with perforated lugs 7 adjacentthe edges of the opening 6 therein,- while the cover '5 is provided withsimilar lugs 8, one pair of which is shown. These lugs, when the coveris placed in position, are adapted to cont-act with each other as shownin Fig. 3. The lugs 7 andS are properforations through which headedbolts 9extend for the purpose of firmly and tightly securing the cover 5in the opening 6.

The casing l is provided at its upper end with flange portions 10forming a seat for a motor 11. The cover 5 is provided with a practicaladvantages apformed in a cover member 5 for filling and 'ing 30 incasing 12 within which is inclosed the gear mechanism by means of whichthe shaft 4: is driven from the shaft of the motor 11.

The opposite edges of the yoke 2 are situated in guide grooves 15oppositely disposed in the casing 1. The yoke is provided with anintegral stem or connecting bar portion 20 to the lower end of which isconnected, preferably integrally, a hammer or other tool 21 providedwith a number of longitudinal grooves 22 in its surface. The hammer isadapted to operate reciprocally in a guiding tubular portion 23 whichpreferably is integral with and projects from the casing 1. As shown, inthe drawing, the portion 23 is of considerably less diameter than'thecasing in which the yoke 2 operates.

The yoke 2 is provided with a quadrantal shaped cam slot 25 into whichextends a crank pin 27 rigidly secured'to the crank disk 3 whichrevolves with uniform speed. A cylindrical sleeve 26 is rotatablymounted vupon the crank pin 27 and adapted to contact with the sides ofthe cam slot 25.

It will, of course, be understood that the shape or form and directionof the cam slot 25 in and with respect to the yoke 2 may be variedwithout departing from the principle of my invention.

Movement of the crank pin 27 in a circle as indicated in Fig. 4 of thedrawing causes said pin to assume different positions in the cam slot 25to effect reciprocatory move.- ment of the yoke 2 and the hammer 21having rigid connection therewith.

In order that access may be had readily to the interior of the casingfor the purpose of changing or renewing the bearing sleeve 26, ifoccasion to do so should arise, and also in order to provide means forretaining the said sleeve in position upon the crank pin 27, I haveprovided a relatively large openthe front side of the casing which isadapted to be closed by a hollow plug 81. In order to retain the plug inposition within the opening, I have provided oppositely disposed pins 32.which project through the Walls thereof and which are held inprojecting position normally by an intermediate coiled spring 33. Theouter ends of these pins 32 contact with inclined' surfaces 3 upon theinner side of the casing 1 adjacent the edge of the opening 30. It willbe seen 7 ends of the yielding pins 32 with the inclined surfaces 34retains the closing plug 31 in position but that it may be readilyremoved by an outward pull thereupon. The inner annular edge of the plug31occupies a position such that at all times some portion thereofcontacts with the sleeve 26 so as to hold the same in pos tion in thecam slot 25.

In order to assure that the sleeve 26 and that the contact of the outerI is adapted to strike the upper end of a reduced stem portion 40 of atool 41, which may be a riveting tool, a rock drill or other tool. Thestem 10 extends througha bushing 42 which is fitted in a reduced opening43 formed in the lower end-of the guiding tubular portion 23. The upperend of the said bushing is provided with a flange 45 seated upon ashoulder 16 intermediate the reduced opening 43 and the larger openingin the tubular portion 23.

It will be noted that the upper end of the stem 10 of the tool 41projects above the upper end of the bushing 42. The presence of thebushing 42 is to protect the tubular extended portion 23 in case themachine should be operated without the presence of the stem 40, or incase the said stem should be too short to prevent the hammer fromstriking against the shoulder 46.

It is noted that the hammer 21 fits somewhat closely the opening in thetubular projection 23 in which it operates. It has been found thatwithout the presence of the grooves 22 in the hammer or some meanswhereby constant communication is maintained between the interior of thecasing 1 and the interior of the tubular portion 23 the, apparatus willnot operate satisfactorily. One reason for this is that upon the downstroke of the hammer the air between the bottom of the hammer and thebottom of the chamber or opening of the tube 23 and the top of the toolstem i0 is compressed and retards the downward stroke of the same or mayprevent it altogether. The presence of the grooves 22, however, preventsthe retention and compression of air or other fluid in the spaceunderneath the hammer and therefore obviates the difficulty mentioned.It

will be understood that the same result may be obtained by providinggrooves in the inner side of the wall of the reduced tubular part 23.

It is apparent that the lengths of the stems 40 of different tools mayvary somewhat so that the positions of the upper ends thereof withrespect to the yoke 2 or with respect to the shoulder or abutment -16may be varied somewhat.

In other words, if the stem 40 of one tool should be somewhat longerthan a corresponding stem of another tool, it is apparent that the upperend thereof would occupy a position somewhat nearer to the yoke 2; or

1 and 5 contain if such stem should be shorter, it is apparent that theupper end would occupy a position farther away from the said yoke. It isapparent, therefore, that means should be provided whereby thedescending or striking movement of the yoke and the hammer connectedtherewith may be interrupted at different points nearer to or fartheraway from the axis or center of movement of the crank pin 27 and block26 carried thereby without interfering with the operation of the device.The means employed by me for that purpose consists in the straighteningout or flattening of the upper portion of the outer wall or side of thecam slot 25 as indicated by the letter a. When thus flattenedout,instead of continuing curved and in parallel relation to the inner wallof the said slot, a certain amount of playof the block 26 or itsequivalent and relative sliding movement between the same and the yoke 2is permitted when the said block is in the upper end portion of the saidslot. Such play also is permitted by the enlargement of the upper end ofthe slot as indicated at 50. The' inner or lower end of the slot is alsoenlarged as indicated at 51.

Assuming that the stem 40 of a tool is shorter than usual or that itshould have been partially removed from the lower end of the tubularmember 23 so that in making its stroke the hammer 21 and yoke 2 movethrough a greater distance than normal or usual :The said yoke ispermitted to move under the inertia of its momentum beyond the positionto which it is actually forced by the crank pin 27, so that the saidyoke actually has a sliding movement or a bodily relative movement withrespect to the said sleeve. At such time if the upper end portion of theouter side wall of the slot 25 were not flattened out as indicated so astopermit a certain amount of play of the sleeve 26 therein, a bindingaction would take place and in all likelihood would cause some injury tothe machine. On the other hand, assuming that the stem is slightlylonger than normal or usual so that the downward or striking movementsof the hammer 21 and yoke 2 are interrupted before they have reached thepoint to which they are normally, positively driven by action of thesleeve 26 in the cam slot 25, it is apparent that there must be acertain amount of play or relative sliding movement between the sleeve26 and the walls of the said slot, otherwise a binding action would take--place which would interfere with the smooth, satisfactory working ofthe device.

At the moment of percussion or striking of the hammer 21 or other memberhavin connection with the yoke 2, the crank pin 27 and its bearingsleeve 26 are situated in the portion of the cam slot 25, one side ofwhich is bounded and formed by the straight ing of the hammer 21 orother member havmg connection with and being operated by the yoke 2, thecrank pin 27 is situated adjacent the lower end of that portion of the76 cam slot 25 having the straight outer side portion a in tangentialrelation to the adjoining part of the quadrantal portion of the camcontour, the said crank pin is wholly free from the shock of the hammerblow or the blow of any other member which may be substituted therefor.The crank pin thus being at the moment of percussion released from theyoke 2 and being free to move independently thereof, and being therebyfree from the re-action effect of the blow or striking of the hammer orother member, the operator of the device or tool is not subjected to thesevere jolting which is characteristic of the operation of pneumatichammers.

By the provision of the flattened upper end portion of the outer wall ofthe cam slot 25, I am enabled to rigidly-and fixedly secure the crankpin -27 to the crank disk 3 and still operate the device successfullyand efliciently with the advantages above pointed out.

It will be understood and observed .that the yoke 2 and parts connectedwith and operated thereby are lifted relatively slowly, og the lifting-movement taking place during practically two-thirds of a revolution ofthe crank pin 27, while the strikingmovement of the cam member 2 iseffected during substantially a movement of one-third of a revolution ofthe said crank pin. Referring to Fig. 4: of the drawing, it will benoted that the striking movement of the cam member 2 is effected by themovement of the crank pin 27 from substantially the 1 o full lineposition shown in that figure to the first dotted line position thereofshown to the right in said figure. The return or lifting movement of thecam member 2 occurs as the result of movement of the crank pin 27 towardthe left from the last mentioned dotted line position to the full lineposition. v

I claim:

1. Incombination, a yoke having a curved cam slot therein, a hammerhaving connection with said yoke, acrank pin extending into said camslot, the said crank pin and slot having relative reciprocatory motionwith respect to eachother, the outer wall of said slot at the regionthereof corresponding to the uppermost portion which is reached by thesaid pin being flattened as described, and a revoluble crank forsupporting the'said crank pin.

2. In combination, a yoke having a curved cam slot therein, thecurvature of the outer wall discontinuing at its upper end prior to thediscontinuance of the curvature of the corresponding portion of theinner wall, a crank pin projecting into the said cam slot and providedwith a-pivoted bearing memher for engaging the walls of said slot, and arevoluble support for said crank pin.

3. Ina power transmitting device, the combination of a casing, a yokesituated in and guided in its reciprocatory movements by said casing,said yoke having a quadrantal shaped cam slot therein, the curvature ofthe upper end portion of the outer wall of said slot terminating at apoint below. the termination of the curvature of the upper end portionof the inner wall of said slot, a crank pin extending into the said cammember operated for causing revoluble moveto effectreciprocasubstanslot, and means ment of said crank pin tory movement ofthe said yoke, tially as described.

4. In a device of the character described, the combination of a powerdriven crank, a percussion tool, and a cam member for actuating saidtool, said member having a cam contour in engagement the said camcontour being made up of a curved part which converts the uniform rotarycrank motion into a quick-return percussive motion and a part having astraight side whereby the said crank is released from percussivere-action.

5. In a device of the character described, the combination of a powerdriven crank, a

thereby, a device actuated by the said cam member, the said cam memberbeing provided with a cam contour proportioned to translate the rotarymotion of the crank into a reciprocating quick-return motion on the partof the said cam member and the said cam contour from the point at whichthe said crank is situated at the moment of impact of the device beingcontinued in a path parallel to the path of movement of said device.

6. In a device of the character described, the combinatiton of a powerdriven crank, a tool, a cam member interposed between the said crank andsaid tool and'having operative connection with each and the said cammember having a quadrantal shaped cam contour proportioned to translatethe rotary motion of the said crank into a reciprocating quick-returnmotion of the said tool, and the outer sideof the said cam contour beingcontinued in a straight line wherewith the said crank,

as mv invention,

by the said crank is released from percussive re-action at the impactend of the stroke of the said tool. 1

7. In a device of the character described, the combination of a motordriven crank, a tool, a cam actuated by the said crank to operate thesaid tool, said cam having a quadrantal cam slot proportioned totranslate the rotary motion of the said crank into a reciprocatingquick-return movement of the said cam member and the said cam contourhaving a part which is parallel to the path of motion of said toolwhereby at the moment of impact of said tool the sa d crank is inreleased relation with respect to the said cam member, substantially asdescribed.

8. In a device of the character described, the-combination of a motordriven crank, a tool, a cam member interposed between the said crank andthe said tool, said member being provided with a curved cam contourproportioned to convert the rotary motion of the crank into areciprocating quick-re- 'which is provided with astraight cam pathwithin which the crank is situated when the said tool reaches the end ofits striking movement, said straight path permitting variation in thelength of the tool stroke.

9. In a device of the character described, the combination of a cammember provided with a curvedcam contour, a crank pin in engagement withsaid cam contour, means for supporting and revolving said crank pin toeflect reciprocatory movement of said cam member, a tool havingconnection with and being actuated by said cam member, and the said cammember being provided with means whereby said crank pin is in releasedrelation with respect thereto at the moment of impact of the said tool.

10. In combination, a cam member having a curved cam slot therein, acrank pin projecting into the said cam slot, and means for causingrevolution of the said crank pin to effect reciprocatory motion of thesaid cam member, and the upper portion of the said cam slot beingenlarged to permit relative sliding movement between the said crank pinand the said cam member whereby the length of stroke of the latter maybe varied without interfering with the move- I ments of the said crankpm.

In testimony that I claim the foregoing v I have hereunto set my handthis 25th day of November, A. D. 1918.

WILLIAM BUHL.

